Switch device having maintained operation



Jan. 7, 1964 E. R. WOLFF 3,117,200

SWITCH DEVICE HAVING MAINTAINED OPERATION Filed Dec. 29. 1961 3 Sheets-Sheet 1 INVENTOR. ERA/5T R. WOLFF,

ATTORNE).

Jan. '7, 1964 E. R. WOLFF 3,117,200

SWITCH DEVICE HAVING MAINTAINED OPERATION Filed Dec. 29, 1961 s Sheets-Sheet 2 //\/v TOR. ERA/s7- WOLF/ A TTORNE Y.

Jan. 7, 1964 E. R. WOLFF 3,117,200

SWITCH DEVICE HAVING MAINTAINED OPERATION Filed Dec. 29, 1961 3 Sheets-Sheet 3 6.2 fi 2a I ,8 ,7

//v VENTOR. ER/vsT R WOLFF,

5y ATTORNEY United States Patent M 3,117,200 SWHTCH DEVICE HAVING MAINTAINED OPERATHUN Ernst R. Wolff, Bloomington, IlL, assignor to General Electric Qompany, a corporation of New York Filed Dec. 29, 1961, er. No. 163,279 9 Claims. (Cl. Nth-86.5)

This invention relates to switches and has particular relation to operating mechanisms for use in a foot operated switch.

Switch devices have heretofore been constructed which include a switch with an actuating mechanism for the switch which is operated in response to movement of an actuator in a given direction for establishing a certain condition of the switch. In many applications it is desirable to provide a switch having a so-called maintained switch operation wherein the switch will be alternately opened and closed by movement of the actuator in a given direction so that during a first direction of actuator movement the switch will be actuated to an open or closed condition, will be maintained in the actuated condition when the actuator is moved in the opposite direction, and will be actuated to the other condition when the actuator is again moved in the first direction. Previous switch designs incorporating maintained switch mechanism have generally incorporated a large number of expensive parts contributing to a high cost and a bulky construction.

It is accordingly a primary object of the present invention to provide a switch mechanism of novel and improved construction for providing a maintained operation of the switch.

It is another object of the invention to provide a novel and improved switch mechanism effective to provide a maintained operation of the switch and including a minimum number of inexpensive parts which are compactly arranged.

It is a further object of the invention to provide a switch including an operating mechanism arranged to control a switch actuating mechanism for providing maintained operation of the switch in response to oscillation of a shaft about its axis which shaft mounts parts of the actuating and operating mechanisms.

in carrying out the invention in one preferred form a switch is provided including a spring-biased, manually movable actuator secured to an oscillatable shaft which oscillates about its axis in response to actuation and release of the actuator. A switch actuating mechanism is loosely mounted on the shaft for rotation with respect thereto and is moved to a first position to displace a switch operating member in one direction in response to actuation of the actuator, is maintained substantially in the first position during release of the actuator, and is moved to a second position to displace the switch operating member in the opposite direction in response to the next actuation of the actuator. To this end a pawl is fixed to the shaft for rotation therewith to effect movement of the actuating mechanism to the first position and actuation of the switch in response to initial actuation of the actuator. A spring-biased, pivotally mounted ratchet cooperates with the actuating mechanism and with the pawl in a manner to hold the actuating mechanism substantially in the first position to maintain the switch Fatented .ian. 7, 1964 in one condition when the actuator is released following initial actuation thereof, and to effect movement of the actuating mechanism to the second position and actuation of the switch to its other condition in response to subsequent actuation of the actuator.

Other objects and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a view in top plan with parts broken away of a switch constructed in accordance with the invention;

FIG. 2 is a view in section taken along the line 2-2 of FIG. 1 showing the switch and the actuating mechanism therefor; and

FIGS. 36 are sectional views taken along the line 33 of FIG. 1 and showing parts of the operating mechanism and a part of the actuating mechanism in various positions for conditions wherein the actuator is respectively elevated, depressed, elevated again, and depressed again.

Referring now to the drawings and particularly FIGS. 1 and 2 there is shown a switch device including a housing represented generally by the numeral 10 and consisting of a base 11 and a cover 12 shown in FIGS. 36 adapted to be detachably secured to the base 11 for enclosing the switch and the operating and actuating mechanisms. Mounted on the base 11 and spaced therefrom is a switch 13 of any suitable construction including a reciprocable operating member 14 adapted to be engaged by switch actuating mechanism represented generally by the numeral 15 to provide open and closed operating conditions of the switch 13. Movement of the actuating mechanism 15 is controlled by operating mechanism represented generally by the numeral 16 which is operated in response to depression and release of an actuator 17 which may comprise a foot operated pedal. The pedal 17 has a generally U-shaped terminal part with spaced legs 13 fixed to opposite ends of a shaft 19 which is journaled for oscillatory movement about its axis by spaced side walls 29 of the base 11. The pedal 17 is biased in a counterclockwise direction as viewed in FIG. 3 to its normal elevated position shown in FIG. 3 by means of a suitable spring 17'.

The switch actuating mechanism 15 is loosely supported by the shaft 19 for pivotal movement with respect thereto in response to movement of parts of the operating mechanism 16. For this purpose a hub 21 is loosely mounted on the shaft 1%, and a rigid arm 22 is secured to the lower portion of the hub 21 as shown in FIG. 2 by means of a screw 23 passing through an opening of the arm 22 at its right hand end into a threaded opening of the hub 21. The left hand end of arm 22 as shown in FIG. 2 rotatably carries an adjusting screw 24 which cooperates with a leaf spring 25 secured to the arm 22 by the screw 23. The spring 25 includes a terminal part 26 engageable with the operating member 14 of switch 13 to reciprocate the member 14 in response to operation of the mechanism 16 as will presently appear. The screw 24 may be adjusted to contact spring 25 and vary the position of terminal 26 relative to operating member 14 to permit adjustment of the pretravel and overtravel of foot pedal 17.

As shown in FIGS. 1 and 3 a rocker arm 27, forming part of the switch actuating mechanism, is loosely mounted on shaft 19 and is spaced axially of hub 21 for pivotal movement with respect to the shaft. The arm 27 carries at its upper surface an axially extending bar 23 which is rigidly fixed to the upper surface of the hub 21 and which serves to directly connect together the arm 27 and the hub 21 so that the hub 21 moves in accordance with movement of the arm 27.

Movement of arm 27 is controlled by means of an operating mechanism including a control member or pawl 3-8 operatively connected to the shaft 1? for movement in response to oscillation of the shaft 19. For this purpose, a bracket 31 is fixed to the shaft 1% for rotation therewith, and the pawl 30 is secured to the bracket 31 by means of a threaded bolt 32 which extends through spaced flanges 33 on the pawl 3t; and into a threaded opening of the bracket 31. A pin 34 is mounted on the bracket 31 and extends laterally therefrom beneath the right hand end 3-5 of pawl 3%} as shown in FIGS. 1 and 3. A spring 36 is coiled about the bolt 32, and its right hand end engages the undersurface of the pin 34 whereas the left hand end of spring 36 engages the undersurface of the pawl 30 so as to bias the pawl 3t? upwardly as viewed in FIG. 3 and to permit pivoting of the pawl relative to bracket 31 in the counterclockwise direction for a purpose appearing hereinafter. The pawl 30 includes an upwardly and outwardly extending tip 37 adapted to engage a shoulder 38 formed on the undersurface of the rocker arm 27 adjacent the left hand end thereof as viewed in FIG. 3 to elevate the arm 27 from the position shown in PEG. 3 in response to depression of the pedal 17 as will presently appear.

Movement of the arm 27 is also controlled by means of a spring biased pivotally mounted control member or ratchet 4%? into the lower end of which a pin 41 frictionally extends and is journaled by means of spaced brackets 42 carried by the base 11. The ratchet 40 is thus pivotally mounted and is biased toward the right or in a clockwise direction as viewed in FIG. 3 by means of a spring 43 coiled about the pin 41 and having one of its ends extending through an opening 44 of the uppermost bracket 4-2 as viewed in FIG. 1, and having the other of its ends passing beneath and engaging a screw 455 threadably carried by the ratchet 46; Under normal at rest conditions of the switch device when the pedal 17 is elevated as shown in FIG. 3, the ratchet 40 is urged in a clockwise direction toward the arm 27 so that right angled projections 46 and 47 of ratchet 40 engage respectively right angled projections 48 and 49 formed on the left hand end of arm 27. For this condition the lower surface of projection 48 of arm 27 engages the upper surface d of projection 47 of ratchet 40. The arm 27 is thus held in its lower position so that spring is also in its lower position and operating member 14 of switch 13 either is slightly spaced from or rests lightly on end 26 of spring 25 and is in its fully extended position to provide either a switch off or a switch on condition. It will be assumed that the switch 13 is olf when the parts are as shown in FIG. 3.

In the present invention the switch mechanism is designed so as to provide a maintained condition of the switch 13 so that when the pedal 17 is first depressed, the switch 13 will be actuated to an on condition, and will remain in such condition when the pedal 17 is thereafter elevated. When the pedal 17 is again depressed, the switch 13 will be actuated to the off condition. In operation, initial depression of pedal 17 is efiective to pivot pawl 3G in a clockwise direction as viewed in FIG. 3 through the agency of the bracket 31 from the position shown in FIG. 3 to that shown in FIG. 4. During such movement pawl 36 engages the shoulder 38 of arm 27 to elevate arm 27 from the position shown in FIG. 3 to that shown in FIG. 4 wherein the projection of arm 27 is disengaged from the ratchet 40. Such movement of arm 27 is transmitted through the bar 25 to the hub 21 which rotates in a corresponding manner to effect elevation of the end 4 26 of spring 25' and therefore elevation of operating member 14 of switch 13 to the position shown in FIG. 2 to actuate the switch to the on position.

When the pedal 17 is released, the pawl 3% is pivoted in a counterclockwise direction from the position shown in FIG. 4 to that illustrated in FIG. 5. During such movement of pawl 3d the arm 27 is also moved in a counterclockwise direction until projection 49 of arm 27 engages the upper surface 50 of projection 47 of ratchet which terminates such movement of arm 27. As pawl St) is so pivoted tip 37 thereof passes over projection 47 of ratchet 4t) whereupon ratchet 40 is snapped in a clockwise direction to the position illustrated in FIG. 5 wherein ratchet 4d and arm 27 engage to positively retain arm 27 against further counterclockwise movement. Although arm 27 is lowered slightly during release of the pedal 17, such movement is insulficient to cause sufficient lowering of spring 25 and member M to actuate the switch 13 off. Therefore, the switch 13 remains in the on condition during release of the pedal 17. Note that tip 37 of pawl 3% is adjacent a shoulder 51 of ratchet 49 after the pedal has been elevated.

When the pedal 17 is again depressed from its position in PEG. 5 to that in FIG. 6, bracket 31 is pivoted in a clockwise direction to move the pawl 3h therewith to pivot ratchet th in a counterclockwise direction and move surface 5f; thereof out of engagement with projection 4") of arm 27 and into engagement with projection 48 of rm 27. It is noted that during this action pawl 30 pivots about the bolt 32 in a counterclockwise direction against the bias of spring as. This action results in counterclockwise movement of arm 27 to the position shown in FIG. 6 which effects corresponding movement of spring 15 to actuate switch 13 to the off condition. When the pedal 17 is again released the various parts will move from the positions shown in FIG. 6 to positions illustrated in FIG. 3.

It is thus seen that a very simple, inexpensive and efficient operating mechanism has been provided for effecting a maintained operation of the switch 13. Also, a single shaft 19 mounts all parts of the mechanisms except the ratchet 4t Although the invention has been described in connection with a switch of the foot operated type, the invention is applicable to switches having actuators of other types and is not to be limited to foot operated switches.

While I have shown and described a particular embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made without departing from my invention in its broader aspects and I, therefore, intend in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a switch device, a switch, a shaft mounted for oscillation about its axis, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to establish a different switch operating condition for each direction of and a certain amount of such pivotal movement, first means connected to the shaft for oscillation therewith to pivot said switch actuating means by said certain amount in one direction in re sponse to shaft oscillation in one direction, and second means mounted for movement relative to said switch actuaiting means to a first position in response to pivoting of the switch actuating means in said one direction to prevent pivot'mg of the switch actuating means by said certai amount in the other direction during the succeeding shaft oscillation in the other direction, said first means being mounted to move said second means to a second position permitting pivoting of the actuating means in said other direction by said certain amount in response to the next succeeding shaft oscillation in said one directron.

2. A device as defined in claim 1 wherein said switch actuating means includes a rocker arm loose on the shaft for engagement with said first and second means, and third means loose on the shaft and connected to the rocker arm for actuating said switch.

3. In a switch device, a switch, a shaft mounted for oscillation about its axis, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to establish a different switch operating condition for each direction of and a certain amount of such pivotal movement, a first member connected to said shaft for oscillation therewith to pivot said actuating means by said certain amount in one direction during shaft oscillation in one direction, and a second spring biased member mounted independently of the shaft for pivotal movement relative to said switch actuating means and relative to said shaft, said second member being biased to engage said actuating means to prevent pivoting of said actuating means by said certain amount in the other direction in response to the succeeding shaft oscillation in the other direction, said first member being mounted to pivot said second member against its bias to a second position permitting pivoting of the actuating means by said certain amount in said other direction during the next succeeding shaft oscillation in said one direction.

4. A device as defined in claim 3 wherein said switch actuating means includes a rocker arm loose on the shaft for engagement by said first and second members, and means loose on the shaft and connected to the rocker arm for actuating said switch.

5. In a foot operated switch device, a switch, a shaft mounted for oscillation about its axis, a spring-biased foot operated pedal connected to the shaft, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to establish a different switch operating condition for each direction of and a certain amount of such pivotal movement, a first member connected to said shaft for oscillation therewith to pivot said actuating means by said certain amount in one direction in response to first depression of said foot pedal, a second member mounted for movement to a first position in response to pivoting of the switch actuating means in said one direction to prevent pivoting of the actuating means by said certain amount in the other direction during elevation of said foot pedal following first depression thereof, said first member being mounted to move said second member to a second position permitting pivoting of the actuating means by said certain amount in said other direction in response to a second depression of said foot pedal following elevation thereof.

6. In a foot operated switch device, a switch, a shaft mounted for oscillation about its axis, a spring-biased foot operated pedal connected to the shaft, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effecive to establish a different switch operating condition for each direction of and a certain amount of such pivotal movement, a first member connected to said shaft for oscillation therewith to engage and pivot said actuating means by said certain amount in one direction during first depression of said foot pedal and to disengage said actuating means during elevation of said foot pedal following said first depression thereof, and a second pivotally mounted member movable by a biasing force into a first position wherein it engages said actuating means in response to disengagement of said first member and said actuating means during elevation of said foot pedal following the first depression thereof to prevent pivoting of said actuating means by said certain amount in the other direction, said first member being mounted to pivot said second member against its bias out of said first position into a second position in response to a second depression of said foot pedal following elevation thereof to permit pivoting of said actuating means by said certain amount in said other direction.

7. In a switch device, a switch having a reciprocable operating member, a shaft mounted for oscillation about its axis, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to reciprocate said switch operating member in a different direction for each direction of and a certain amount of such pivotal movement, said actuating means including a leaf spring engageable with said operating member to effect reciprocation thereof, a first member connected to said shaft for oscillation therewith to pivot said actuating means by said certain amount in one direction during shaft oscillation in one directon, and a second spring-biased member mounted for pivotal movement relative to said actuating means and relative to said shaft, said second member being mounted for pivotal movement about an axis spaced from and generally parallel to the axis of said shaft, said second member being biased to engage said actuating means to prevent pivoting thereof by said certain amount in the other direction in re sponse to the succeeding shaft oscillation in the other direction, said first member being mounted to pivot said second member against its bias to a second position permit-ting pivoting of the actuating means by said certain amount in said other direction during the next succeeding shaft oscillation in said one direction.

8. In a switch device, a switch, a shaft mounted for oscillation about its axis, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to estabhsh a different switch operating condition for each direction of and a certain amount of such pivotal movement, said switch actuating means including an arm extending transversely of the shaft and having a pair of right angled projections, a first member connected to said shaft for oscillation therewith to engage one of the projections of said arm to pivot said actuating means by said certain amount in one direction during shaft oscillation in one direction, and a second spring biased member mounted for pivotal movement relative to said actuating means and relative to said shaft, said second member being mounted for pivotal movement about an axis spaced from and generally parallel to said shaft, said second member also having two right angled projections and being biased for pivotal movement towards said shaft so that one of its projections engages one of the projections of said arm to prevent pivoting of said arm by said certain amount in the other direction in response to the succeeding shaft oscillation in the other direction, said first member being mounted to engage said one of the projections of the second member to pivot said second member against its bias to a second position wherein said one of the projections of the second member is moved clear of said one projection of the arm to permit pivoting of the arm by said certain amount in said other direction during the next suceeding shaft oscillation in said one direction.

9. In a switch device, a switch having a reciprocable operating member, a shaft mounted for oscillation about its axis, switch actuating means mounted loose on the shaft for pivotal movement relative to the shaft and effective to reciprocate said switch operating member in a different direction for each direction of and a certain amount of such pivotal movement, said actuating means including a leaf spring engageable with said operating member to effect reciprocation thereof, said switch actuating means including an arm extending transversely of the shaft and having a pair of right angled projections, 11 first member connected to said shaft for oscillation therewith to engage one of the projections of said arm to pivot said actuating means by said certain amount in one direction during shaft oscillation in one direction, and a second spring biased member mounted for pivotal movement relative to said actuating means and relative to said shaft, said second member being mounted for pivotal movement about an axis spaced from and generally parallel to said shaft, said second member also having two right angled 5? E's projections and being biased for pivotal movement topivoting of the arm by said certain amount in said other Wards said shaft so that one of its projections engages direction during the next succeeding shaft oscillation in one of the proiections of said arm to prevent pivoting of said one direotion. said arm by said certain amount in the other direction in 7 response to the succeeding shaft oscillation in the other di- 5 References Cited in the fil f this Patent rection, said first member being mounted to engage said UNITED STATES PATENTS one of the projections of the second member to pivot said I second member against its bias to a second position gfiwenberg i i 5 wherein said one of the projections of the second member 9 may is moved clear of said one projection of the arm to permit 10 Deans July 105 1934 

1. IN A SWITCH DEVICE, A SWITCH, A SHAFT MOUNTED FOR OSCILLATION ABOUT ITS AXIS, SWITCH ACTUATING MEANS MOUNTED LOOSE ON THE SHAFT FOR PIVOTAL MOVEMENT RELATIVE TO THE SHAFT AND EFFECTIVE TO ESTABLISH A DIFFERENT SWITCH OPERATING CONDITION FOR EACH DIRECTION OF AND A CERTAIN AMOUNT OF SUCH PIVOTAL MOVEMENT, FIRST MEANS CONNECTED TO THE SHAFT FOR OSCILLATION THEREWITH TO PIVOT SAID SWITCH ACTUATING MEANS BY SAID CERTAIN AMOUNT IN ONE DIRECTION IN RESPONSE TO SHAFT OSCILLATION IN ONE DIRECTION, AND SECOND MEANS MOUNTED FOR MOVEMENT RELATIVE TO SAID SWITCH ACTUATING MEANS TO A FIRST POSITION IN RESPONSE TO PIVOTING OF THE SWITCH ACTUATING MEANS IN SAID ONE DIRECTION TO PREVENT PIVOTING OF THE SWITCH ACTUATING MEANS BY SAID CERTAIN AMOUNT IN THE OTHER DIRECTION DURING THE SUCCEEDING SHAFT OSCILLATION IN THE OTHER DIRECTION, SAID FIRST MEANS BEING MOUNTED TO MOVE SAID SECOND MEANS TO A SECOND POSITION PERMITTING PIVOTING OF THE ACTUATING MEANS IN SAID OTHER DIRECTION BY SAID CERTAIN AMOUNT IN RESPONSE TO THE NEXT SUCCEEDING SHAFT OSCILLATION IN SAID ONE DIRECTION. 